If you introduce infant formula to your baby, you’ll probably want to be on the alert for signs of an allergy, especially if allergies run in your–or the baby’s father’s–family. Most infant formula includes cow’s milk or soy products in the ingredients. In cases of infant formula allergies, cow’s milk protein is the most common allergen. Still, allergies to infant formula are not all that common; according to the U.S. Department of Agriculture, less than 3% of babies in the United States have an allergy to milk protein. Half of the babies who are sensitive to cow’s milk protein also turn out to react badly to soy. Soy-based formula is not necessarily the solution if your baby does turn out to have a dairy allergy. Check with your baby’s physician before switching to a hypoallegenic formula.
It may reassure you to know that there’s good chance your baby will outgrow an allergy to infant formula within a few years.
If your baby’s skin develops a rash, hives or the dry, flaky patches of skin called eczema, tell your doctor. A diaper-rash like ring around his rectum that doesn’t clear up with diaper rash cream may also be symptomatic of infant formula allergies.
Reflux and Vomiting
Most babies spit up, especially in the first few months—this is normal and due to the immaturity of their digestive tracts. However, if your baby repeatedly forcefully vomits or spits up a lot of her formula (a sign of excessive reflux), this may be cause for concern.
If you’re switching your baby to infant formula from breast milk, expect the stools to smell and look different. But if the stools smell foul or are especially hard or loose, this could be a heads-up that allergies to infant formula are playing a part. Be sure to talk with the pediatrician in cases of blood in the stool or diarrhea that occurs several times a day for several days in a row.
Babies who are allergic to infant formula may get fussy during or after their feedings and cry, squirm or show other signs of digestive discomfort. Crying incessantly, as with colic, may suggest your baby is feeling gassy or has abdominal pain. These may be normal, or they may be signs of an allergy to formula. If you are wondering whether your baby has a lactose intolerance (which is not the same as an allergy), know that the U.S. Department of Agriculture advises that lactose intolerance is extremely rare in babies.
Regular gastric problems such as vomiting and diarrhea may prevent your baby’s growing as fast as he should. Failure to thrive is not normal and should be brought to a doctor’s attention immediately.
Nasal congestion, asthma, wheezing, shortness of breath, mucus in the throat or nose and other respiratory abnormalities that aren’t attributable to a cold may be signs of an allergic reaction to milk protein.
Babies who suffer from formula allergies may experience discomfort that prevents their sleeping soundly. If your baby is having problems with sleeplessness, let her pediatrician know.